Research heats the city
The energy company Kraftringen is currently constructing the world’s largest low temperature district heating network in Brunnshög in Lund. The background to this major investment is the desire to make the most efficient use of the low temperature residual heat available in Brunnshög. The technology is well adapted and very well suited to the modern, energy-efficient homes and businesses that will be constructed in Brunnshög.
Low temperature residual heat (30-50°C) is available in large quantities in Lund, generated from various kinds of activities and facilities. Residual heat is a product that is created in connection with activities that have a need for cooling. (Delivering cooling to a business or other activity is namely the same thing as removing heat from it). Kraftringen already has access to residual heat from the MAX IV research facility in Brunnshög, which has been in operation since 2016 and has a very large need for cooling. The residual heat from the MAX IV facility is currently transferred to Lund’s existing district heating network, after being heated to a temperature of around 90⁰C with the help of heat pumps. Since September 2019, the heat is also utilised directly (almost entirely without an increase in temperature) in the new, separate, low temperature network that has been constructed in Brunnshög at a constant temperature of 65⁰C.
The installation of the network and access to prime low temperature residual heat from sources such as MAX IV, means that Kraftringen is able to supply new buildings in Brunnshög with heating from the very start. As the expansion of Brunnshög continues, an increasing amount of the heat from MAX IV will be used in the low temperature network instead of Lund’s high temperature network. This is a positive development, as the lower temperature entails more efficient production, reduced heat losses and the ability to use distribution pipes made from plastic rather than classic steel pipes. All of this means that Brunnshög’s district heating customers can be offered a district heating price that is lower than normal.
In addition to heating homes and business premises, the residual heat and the low temperature network will also be able to be utilised for purposes for which heating is not usually used at present. For example, the technology will be used to heat the ground at Brunnshög’s tram stops during the winter, in order to eliminate the need for snow removal and avoid slush and slippery surfaces. We are also investigating other applications and technologies in the EU-financed innovation project COOL DH.